The details of the origin of life on Earth are unknown, but lifeforms must have originated and developed over a long period of chemical evolution from simple inorganic and organic compounds. This required consistent energy from our Sun and other local resources. Eventually, chemiosmosis took hold so that the energy of light, heat, and exothermic reactions could be transduced to endothermically form more complex molecules as in the carbon building of lipids. These molecules became lipid membrane structures to contain chemical reactions, carbohydrates for metabolic reactions, proteins to make catalytic enzymes, and nucleotides to provide high-energy phosphates and to form ATP, DNA, and RNA. Of all the 100 or so nucleobases found in Nature, only 5 were utilized and only 20 or so of the available amino acids were selected by the advent of the proposed last universal common ancestor. While this was likely a bottoms-up approach to prebiotic biosynthesis, parts of each of these groups paired up to make more complex, functioning macromolecules, as in ATP or DNA, so chemical evolution simplified the formation of compounds that would be needed for the onset of chemical replication, transcription of the genetic information, and translation of the genetic code to make polypeptides. In a broad view, some basic chemical compounds likely came from the cosmos and some molecules were likely formed in hydrothermal vents while some macromolecules were formed by condensation and polymerization, which probably occurred on land and sea in wet-dry cycles. Important events that led to life include development of semi-permeable lipid membranes, carbon building via acetate and co-enzyme A, ascent of adenine as the preferred base for catalytic activity, generation of high-energy phosphate bonds to store energy, onset of a suitable chemiosmosis mechanism with oxidation and phosphorylation, dinucleotide cofactors to facilitate electron transfer and group transfer reactions, selection of a standard genetic code, genesis of the ribozyme with a peptidyl transfer center to match RNA with polypeptides, and naturally, a continuous supply of energy from our Sun.